Massive attack

SOMETIMES the smallest of signs heralds the greatest of changes. Last June, the Japanese-American SuperKamio-kande team announced that at least one of the three ghostly particles known as neutrinos must have some mass-perhaps less than a millionth that of an electron. Yet this tiny quantity has profound consequences.

"It's a fantastically important result, the biggest breakthrough for particle physics in over a decade," says Joel Primack, a physicist from the University of California, Santa Cruz. In the Standard Model of particle physics, none of the three varieties-the electron neutrino, the muon neutrino, and the tau neutrino-has any mass at all.

But if the Standard Model is wrong, what will replace it? The answer depends on exactly how hefty each kind of neutrino is. Their masses will tell us much about the next generation of fundamental theories. And they are also important for cosmology, as different neutrino masses would have had ...

To continue reading this article, subscribe to receive access to all of newscientist.com, including 20 years of archive content.

To continue reading this article, log in or subscribe to New Scientist

App + web

Web

Smartphone

Tablet

$25.99 - Save 65%

12 issues for $2.17 per issue

with continuous service

Print + web

Print

Web

$28.99 - Save 61%

12 issues for $2.42 per issue

with continuous service

Print + app + web

Print

Web

Smartphone

Tablet

$39.99 - Save 73%

12 issues for $3.33 per issue

with continuous service

Web

Web only

$49.99

30 day web pass

Prices may vary according to delivery country and associated local taxes.